Van der Pol Approximation Applied to Wien Oscillators

This paper presents a nonlinear analysis of the Wien type oscillators based on the Van der Pol approximation. The steady-state equations for the key parameters, frequency and amplitude, are derived and their sensitivities to ambient temperature are discussed. The added value of this work is to present an analytical method to obtain the fundamental characteristics of the Wien type oscillators and to relate these characteristics with the circuit parameters in a simpler manner. The simulation results confirm the amplitude and frequency equations, and confirm that the amplitude is controlled by the limiter circuit.